The invention is directed to active materials extracted from plants of the family Hypoxidaceae.
The plant family of Hypoxidaceae belongs to the monocotyledons and includes relatively few genera which, however, occur world wide except for most parts of Europe and northern Asia. Member genera of the Hypoxidaceae family are, for example, Curculigo, Empodium, Hypoxis, Spiloxene, Rhodohypoxis, Campynema, Campynemanthe, Pauridia and Xiphidium.
Until now relatively little has been published about this plant family and its components. In these publications it has been shown that the members of this family predominantly contain various sugars and sugar derivatives such as mucilage hemicellulose, polysaccharides and specific sugars such as xylose, glucose, mannose, fructose, sucrose and glucuronic acid. Phenolic compounds have also been detected such as for example coumaric acid, caffeic acid, ferulic acid and ellagic acid as well as quercetin. Furthermore, there are indications of the presence of anthocyanidines; it has also been asserted that chelidonic acid is present, although there are doubts about this. In this plant family alkaloids or saponins, have not been found, but there have been numerous references to the occurrence of sterols, sterol glycosides, and steroid glycosides.
Until now there have been no authenticated reports that toxic compounds are present in the plants. It appears on the contrary that some species have been used in the folk medicine of different countries and even as a food, although generally only in times of famine and other emergencies.
Only in recent times has reference been made to the fact that members of the Hypoxidaceae family have surprising medicinal properties. For example, the production of extracts of the Hypoxis genus is described in the German OS 2,015,877 corresponding to the British Pat. No. 1,259,503, the German OS 2,251,695 and the German OS 2,312,285 corresponding to the British Pat. No. 1,417,272 and the U.S. Pat. No. 3,933,789. In these publications reference has been made to the fact that the activity of the extracts depends on sterol glycosides or steroid glycosides in them and that these extracts show activity especially in the treatment of benign prostate hypertrophy and its attendant phenomena.
With respect to the production of extracts from Hypoxis species the German OS 2,015,877 refers only to the extraction of comminuted fresh or previously dried tubers or corms with water, ethanol or aqueous ethanol. In contrast the German OS 2,251,695 specifies that the corms of the Hypoxis species used have to be dried at temperature not exceeding 40.degree. C. before they are extracted. According to this publication the extraction can also be carried out with, amongst others, a mixture of water and lower alcohols.
On the other hand the German OS 2,312,295 refers in detail to the absolute necessity that sterolin degrading enzymes in the corms have to be destroyed by heating them to at least 60.degree. C. before carrying out the actual extraction. In addition it is shown that especially sterolin rich extracts can only be obtained if the extraction is carried out by boiling the plant material in water. In contrast the extraction with 60% ethanol yields an extract which contains only traces of sterolins and sterolin compounds.